1. Field of the Invention
This invention relates to a light-emitting device.
2. Background Art
Light-emitting devices used in illumination and display devices and being capable of emitting visible light are often based on the surface-mounted device (SMD) structure which facilitates attachment to a circuit board.
In the SMD structure, a light-emitting element is bonded onto a lead frame exposed into a recess provided in a resin molded body. Furthermore, a sealing resin material is filled in the recess so as to cover the light-emitting element. The resin typically has a larger linear expansion coefficient than the lead frame made of a metal. Combined with the difference in material, this makes insufficient the adhesiveness therebetween.
Particularly for a light-emitting element with high power consumption, it is necessary to keep good heat dissipation while preventing delamination between the lead and the resin molded body.
JP-A 2001-518692 (Kohyou) discloses an example technique related to a surface-mounted light-emitting device. In this example, a plurality of external terminals protruding from a cover can be simultaneously mounted on a circuit board and are formed so as to protrude from a molded body as thermally conductive terminals.
However, even this example is not sufficient to keep good heat dissipation while preventing delamination between the lead and the resin molded body.